1. Field of the Invention
The present invention relates to electrical and electronic systems and methods. More specifically, the present invention relates to systems and methods for processing GPS and other signals.
2. Description of the Related Art
The Global Positioning System (GPS) is a network of satellites that transmits information in signals, which when received and decoded, allow a receiver to accurately fix its position within a coverage area. For military applications, GPS allows self-guided weapons to find targets with heretofore unknown degrees of accuracy.
The GPS is inherently vulnerable to inadvertent and overt jamming and spoofing, necessitating the need to provide additional jamming and prevention techniques to enhanced the robustness of this system. A large number of anti-jam processing techniques have been developed for GPS receivers ranging from excision filters to analog adaptive processing and digital adaptive processing techniques. Generally, these techniques have a number of shortcomings that drive performance, cost, power, and size that make them less attractive for advanced weapon systems.
For example, excision filters and analog adaptive processing anti-jam GPS designs are limited in the number and type (wideband, narrowband, pulse, etc.) of jammers that may be handled.
To overcome the shortcomings of these techniques, the use of Space Frequency Adaptive Processing (SFAP) and Space Time Adaptive Processing (STAP) have emerged as promising candidate anti-jam technologies for GPS. However, these approaches also have a shortcoming in that both require the use of precisely matched antenna elements, diplexer channel, RF downconverter channels, RF and IF filters, which increases system cost and limits performance over the wide temperature ranges experienced by weapon systems.
Hence, a need remains in the art for a system or method for enhancing the robustness of GPS. Specifically, a need remains in the art for a system or method for reducing the vulnerability of GPS to inadvertent and overt jamming and spoofing.